Microled display

ABSTRACT

A display, system and method of providing a display are described. The display includes sets of microLEDs. Each set of microLEDs corresponds to one of a plurality of pixels of the display and produces a combination of light that forms a color of the corresponding one of the pixels. Lenses control an emission angle and emission profile of the light emitted by the sets of microLEDs. Each set of microLEDs has a red microLED that emits red light, a green microLED that emits green light, a blue microLED that emits blue light, and another microLED that emits light along a red-green locus. The red-green locus light is selected to enhance efficiency at a white point to compensate for reduced emission from the red microLED dependent on a size of the red microLED.

PRIORITY

This application is a continuation of U.S. patent application Ser. No.17/129,540, filed on Dec. 21, 2020, which claims the benefit of priorityto U.S. Provisional Patent Application Ser. No. 62/953,331, filed Dec.24, 2019, which are incorporated herein by reference in theirentireties.

TECHNICAL FIELD

The present disclosure relates generally to displays and, morespecifically, to a microLED display for improved efficiency.

BACKGROUND

MicroLED is an emerging display technology that employs arrays ofmicroscopic LEDs to implement the individual pixels of the display.Compared to LCD displays, microLED displays offer improved contrast,response times, and energy efficiency. OLED and microLED displays may beadvantageously used to implement small, low-energy devices, such assmartwatches and smartphones, for example. OLED and microLED technologyboth offer greatly reduced energy requirements compared to conventionalLCD displays while simultaneously offering a high contrast ratio. UnlikeOLED, microLED can be based on indium gallium nitride (InGaN) and/oraluminum indium gallium phosphide (AlInGaP) LED technology, which offersa far greater (e.g., up to 30 times greater) total brightness than OLED,as well as higher efficiency (which may be expressed in cd/W, c/A,nits/W, or nits/A) and lower power consumption than OLED. UnlikemicroLED, OLED also suffers from screen burn-in.

For a display with a sufficiently large color gamut, three colors areused: red, green, and blue. One of the challenges is to make efficientLEDs at the micrometer level (e.g., microLEDs) and for red, this isespecially difficult. At the micrometer level, the external quantumefficiency (EQE) for green and blue can be as high as 20%, while forred, the EQE is typically around 5%. In particular, the low EQE of redmicroLEDs, has a negative impact on the achievable white displayefficiency. For white, a common color balance is a few percent bluelight, about ⅔ green light, and about ⅓ red light. When converting thisto electrical power, the low efficiency of red microLEDs changes thissituation dramatically. In electrical power, a color balance for whiteis more along the lines of ⅛ blue, ⅛ green, and ¾ red, which means thatthe efficiency of the display is dominated by the (relatively poor)performance of the red LEDs.

BRIEF DESCRIPTION OF THE FIGURES

To provide a more complete understanding of the present disclosure andfeatures and advantages thereof, reference is made to the followingdescription, taken in conjunction with the accompanying figures, whereinlike reference numerals represent like parts, in which:

FIG. 1 illustrates an example unit cell corresponding to one or morepixels in a display implemented using red, green, and blue microLEDs;

FIG. 2 illustrates another example unit cell corresponding to one ormore pixels in a display implemented using red, green, blue, and yellowmicroLEDs in accordance with embodiments described herein;

FIG. 3A illustrates a top schematic view of a portion of a microLEDdisplay implemented using red, green, blue, and yellow microLEDs inaccordance with embodiments described herein;

FIG. 3B is a side view of the microLED display shown in FIG. 3B;

FIGS. 4A-4D illustrate various systems into which a microLED display inaccordance with embodiments described herein may be incorporated;

FIG. 5 is an International Commission on Illumination (CIE) 1931chromaticity diagram for use in illustrating embodiments describedherein comprising a display implemented using red, green, blue, andyellow microLEDs;

FIG. 6A is a graph illustrating an effective external quantum efficiency(EQE) along a red-green locus for a display implemented using red,green, and blue microLEDs;

FIG. 6B is a graph illustrating an EQE along a red-green locus for adisplay implemented using red, green, and blue microLEDs;

FIG. 6C is a graph illustrating an EQE gain along a red-green locus fora display implemented using red, green, and blue microLEDs;

FIG. 6D is a graph illustrating lumens per watt (lm/W) gain along ared-green locus for a display implemented using red, green, and bluemicroLEDs;

FIG. 7A is a graph illustrating lm/W gain for a display implementedusing red, green, and blue microLEDs to represent pixels thereof;

FIG. 7B is a graph illustrating lm/W gain for a display implementedusing red, green, blue, and yellow microLEDs to represent pixelsthereof;

FIG. 8 is a block diagram illustrating an example data processing systemthat may be configured to implement at least portions of a displayimplemented using microLEDs in accordance with embodiments describedherein;

FIG. 9 is a flow chart illustrating example operations for a displayimplemented using red, green, blue, and yellow microLEDs in accordancewith embodiments described herein; and

FIG. 10 is another block diagram illustrating an example system forimplementing at least portions of a display implemented using microLEDsin accordance with embodiments described herein.

DETAILED DESCRIPTION

The systems, methods and devices of this disclosure each have severalinnovative aspects, no single one of which is solely responsible for theall of the desirable attributes disclosed herein. Details of one or moreimplementations of the subject matter described in this specificationare set forth in the description below and the accompanying drawings.

For purposes of illustrating the disclosures described herein, it mightbe useful to understand phenomena that may be relevant to variousembodiments thereof. The following foundational information may beviewed as a basis from which the present disclosure may be properlyexplained. Such information is offered for purposes of explanation onlyand, accordingly, should not be construed in any way to limit the broadscope of the present disclosure and its potential applications.

Some embodiments provide a display including a plurality of sets ofmicroLEDs, wherein each set of microLEDs corresponds to one of aplurality of pixels of the display, wherein each set of microLEDsproduces a combination of light perceived by a viewer as a color of thecorresponding one of the pixels and a plurality of lenses forcontrolling an emission angle and emission profile of the light emittedby the sets of microLEDs, wherein each set of microLEDs comprises amicroLED that emits red light, a microLED that emits green light, amicroLED that emits blue light, and a microLED that emits light along ared-green locus.

Some embodiments further provide an apparatus including a displaycomprising a plurality of sets of microLEDs, wherein each set ofmicroLEDs corresponds to one of a plurality of pixels of the display,wherein each set of microLEDs produces a combination of light perceivedby a viewer as a color of the corresponding one of the pixels and aplurality of lenses for controlling an emission angle and emissionprofile of the light emitted by the sets of microLEDs, wherein each setof microLEDs comprises a microLED that emits red light, a microLED thatemits green light, a microLED that emits blue light, and a yellowmicroLED. The apparatus further includes a display controller forcontrolling an intensity distribution of each of the plurality of setsof microLEDs in accordance with video data signals received by thedisplay controller thereby to control a color produced by each of theplurality of sets of microLEDs and thereby control a color of thecorresponding one of the plurality of pixels.

Some embodiments still further provide a method for presenting an imageon a display, the method comprising providing a plurality of sets ofmicroLEDs, wherein each of the sets of microLEDs emits light of atunable color and intensity, wherein each set of microLEDs comprises amicroLED that emits red light, a microLED that emits green light, amicroLED that emits blue light, and a microLED that emits light along ared-green locus; and controlling an intensity distribution of each ofthe plurality of sets of microLEDs in accordance with video data signalsto control a color produced by each of the plurality of sets ofmicroLEDs.

Embodiments disclosed herein may be particularly advantageous forproviding an energy efficient, high contrast, highly responsive microLEDdisplay. In particular, embodiments disclosed herein include adding atleast a fourth microLED that emits light at a visible wavelengthproximate the red-green locus (e.g., yellow/amber), thereby to improvethe efficiency of the display by reducing the contribution of the red(i.e., least efficient) microLED. Other features and advantages of thedisclosure will be apparent from the following description and theclaims.

As will be appreciated by one skilled in the art, aspects of the presentdisclosure, in particular aspects of a microLED display describedherein, may be embodied in various manners—e.g. as a method, a system, acomputer program product, or a computer-readable storage medium.Accordingly, aspects of the present disclosure may take the form of anentirely hardware embodiment, an entirely software embodiment (includingfirmware, resident software, micro-code, etc.) or an embodimentcombining software and hardware aspects that may all generally bereferred to herein as a “circuit,” “module” or “system.” Functionsdescribed in this disclosure may be implemented as an algorithm executedby one or more hardware processing units, e.g. one or moremicroprocessors, of one or more computers. In various embodiments,different steps and portions of the steps of each of the methodsdescribed herein may be performed by different processing units.Furthermore, aspects of the present disclosure may take the form of acomputer program product embodied in one or more computer readablemedium(s), preferably non-transitory, having computer readable programcode embodied, e.g., stored, thereon. In various embodiments, such acomputer program may, for example, be downloaded (updated) to theexisting devices and systems (e.g. to the existing display systemsand/or their controllers, etc.) or be stored upon manufacturing of thesedevices and systems.

In the following detailed description, various aspects of theillustrative implementations may be described using terms commonlyemployed by those skilled in the art to convey the substance of theirwork to others skilled in the art. For example, the term “connected”means a direct electrical or magnetic connection between the things thatare connected, without any intermediary devices, while the term“coupled” means either a direct electrical or magnetic connectionbetween the things that are connected, or an indirect connection throughone or more passive or active intermediary devices. The term “circuit”means one or more passive and/or active components that are arranged tocooperate with one another to provide a desired function. The terms“substantially,” “close,” “approximately,” “near,” and “about,”generally refer to being within +/−20%, preferably within +/−10%, of atarget value based on the context of a particular value as describedherein or as known in the art. Similarly, terms indicating orientationof various elements, e.g., “coplanar,” “perpendicular,” “orthogonal,”“parallel,” or any other angle between the elements, generally refer tobeing within +/−5-20% of a target value based on the context of aparticular value as described herein or as known in the art.

The terms such as “over,” “under,” “between,” and “on” as used hereinrefer to a relative position of one material layer or component withrespect to other layers or components. For example, one layer disposedover or under another layer may be directly in contact with the otherlayer or may have one or more intervening layers. Moreover, one layerdisposed between two layers may be directly in contact with one or bothof the two layers or may have one or more intervening layers. Incontrast, a first layer described to be “on” a second layer refers to alayer that is in direct contact with that second layer. Similarly,unless explicitly stated otherwise, one feature disposed between twofeatures may be in direct contact with the adjacent features or may haveone or more intervening layers.

For the purposes of the present disclosure, the phrase “A and/or B”means (A), (B), or (A and B). For the purposes of the presentdisclosure, the phrase “A, B, and/or C” means (A), (B), (C), (A and B),(A and C), (B and C), or (A, B, and C). The term “between,” when usedwith reference to measurement ranges, is inclusive of the ends of themeasurement ranges. As used herein, the notation “AB/C” means (A), (B),and/or (C).

The description uses the phrases “in an embodiment” or “in embodiments,”which may each refer to one or more of the same or differentembodiments. Furthermore, the terms “comprising,” “including,” “having,”and the like, as used with respect to embodiments of the presentdisclosure, are synonymous. The disclosure may use perspective-baseddescriptions such as “above,” “below,” “top,” “bottom,” and “side”; suchdescriptions are used to facilitate the discussion and are not intendedto restrict the application of disclosed embodiments. Unless otherwisespecified, the use of the ordinal adjectives “first,” “second,” and“third,” etc., to describe a common object, merely indicate thatdifferent instances of like objects are being referred to, and are notintended to imply that the objects so described must be in a givensequence, either temporally, spatially, in ranking or in any othermanner.

In the following detailed description, reference is made to theaccompanying drawings that form a part hereof, showing, by way ofillustration, some of the embodiments that may be practiced. In thedrawings, same reference numerals refer to the same or analogouselements/materials so that, unless stated otherwise, explanations of anelement/material with a given reference numeral provided in context ofone of the drawings are applicable to other drawings whereelements/materials with the same reference numerals may be illustrated.For convenience, if a collection of drawings designated with differentletters are present, e.g., FIGS. 2A-2C, such a collection may bereferred to herein without the letters, e.g., as “FIG. 2 .” Theaccompanying drawings are not necessarily drawn to scale. Moreover, itwill be understood that certain embodiments can include more elementsthan illustrated in a drawing, certain embodiments can include a subsetof the elements illustrated in a drawing, and certain embodiments canincorporate any suitable combination of features from two or moredrawings.

Various operations may be described as multiple discrete actions oroperations in turn in a manner that is most helpful in understanding theclaimed subject matter. However, the order of description should not beconstrued as to imply that these operations are necessarily orderdependent. In particular, these operations may not be performed in theorder of presentation. Operations described may be performed in adifferent order from the described embodiment. Various additionaloperations may be performed, and/or described operations may be omittedin additional embodiments.

In some examples provided herein, interaction may be described in termsof two, three, four, or more electrical components. However, this hasbeen done for purposes of clarity and example only. It should beappreciated that the devices and systems described herein can beconsolidated in any suitable manner. Along similar design alternatives,any of the illustrated components, modules, and elements of theaccompanying drawings may be combined in various possibleconfigurations, all of which are clearly within the broad scope of thepresent disclosure. In certain cases, it may be easier to describe oneor more of the functionalities of a given set of flows by onlyreferencing a limited number of electrical elements.

The following detailed description presents various descriptions ofspecific certain embodiments. However, is to be understood that otherembodiments may be utilized, and structural or logical changes may bemade without departing from the scope of the present disclosure. Ingeneral, the innovations described herein can be embodied in a multitudeof different ways, for example, as defined and covered by the claimsand/or select examples, and the following detailed description is not tobe taken in a limiting sense.

As will be described in greater detail hereinbelow, some examples of thepresent disclosure provide a unit cell having several LEDs (inparticular, microLEDs), each of which may be addressed individually orin groups. In one embodiment, microLEDS can be sized to be significantlysmaller than a lens positioned to receive light from the microLEDs.Multiple microLEDS can be positioned under the same lens, with at leastsome microLEDS being positioned away from an optical axis of the lens.Depending on their position with respect to the lens, each light beamemitted from the microLEDS will typically have a slightly differing beamdirection. Alternatively, microLEDS can fitted with similarly sizedintegral lens and differing beam directions can be provided bymodifications to lens characteristics or direction of microLED lightemission. Additionally, the microLEDs can be independently activated (orturned on), deactivated (or turned off), or “dimmed” to an intermediatevalue. These features enable the beam or beams emitted from the unitcells to appear to be steered without physically moving either themicroLEDS or the lens. In addition to beam steering, beam intensity canbe increased or decreased by increasing or decreasing the number ofmicroLEDS used to form a beam. This allows for highlighting a locationor turned down to reduce or eliminate light where it is not desired.Beam steering can save energy by only generating the light that isneeded. In some embodiments, complex dynamic lighting effects based onbeam steering can be created and may be used for directing userattention or for artistic effect.

FIG. 1 illustrates a unit cell 100 of a microLED array for representinga pixel in a stereoscopic display implemented using microLEDs inaccordance with embodiments described herein. As used herein, the term“microLED” can refer to microscopic III-V semiconductor or othercompound semiconductor light emitters, such as indium gallium nitride(InGaN)-based and/or aluminum indium gallium phosphide (AlInGaP)-basedLEDs. Some microLED embodiments do not use an encapsulation layer andcan be sized on the order of 1/100^(th) the size of conventional LEDs.The term “microLED display” refers to an emissive display implementedusing arrays of microLEDs in which the picture elements, or pixels, arealso the light source. Emissive display technologies do not require aseparate backlight layer, enabling them to be thinner than LCDs. Invarious embodiments, the display may be implemented as a monolithic diedisplay, a segmented display, and/or a pixelated display. A microLEDarray may include a plurality of pixels arranged as a matrix. Thus,microLEDs can be defined on a monolithic semiconductor substrate, formedon segmented, partially, or fully divided semiconductor substrate, orindividually formed or panel assembled as groupings of microLEDs. ThemicroLED array may comprise independently operable discrete microLEDsarranged as an array or one or more segmented monolithic microLED arrayin which the segments may be independently operable. A segmentedmonolithic microLED array is a monolithic semiconductor diode structurein which trenches passing partially but not entirely through thesemiconductor diode structure define electrically isolated segments. Theelectrically isolated segments remain physically connected to each otherby portions of the semiconductor structure.

In some embodiments, the light emitting array can include small numbersof microLEDs positioned on substrates that are centimeter scale area orgreater. In some embodiments, the plurality of pixels may be arranged inregular shape, such as a rectangle or circle, although other shapes maybe used. Pixels can be of the same size, of differing sizes, orsimilarly sized and grouped to present larger effective pixel size. ThemicroLED array may include thousands or millions of light emitting LEDspositioned together on centimeter scale area substrates or smaller. Eachpixel may comprise a microLED as described herein. The microLED arraycan support high density pixels having a lateral dimension of less than100 μm by 100 μm. The microLED array can support high density pixelshaving a lateral dimension of less than 100 μm by 100 μm. As usedherein, a microLED refers to an independently-controllable LED.Alternatively, or in addition, a microLED refers to an LED havinglateral dimensions of 1 to 100 μm. For example, a microLED array mayhave dimensions of about 50 μm in diameter or width.

As shown in FIG. 1 , in an example embodiment, the unit cell 100 (whichmay also be referred to as a “hyper pixel”) includes a number of sets ofmicroLEDs 102A-102C disposed on a substrate 103. The microLED array maycontain a number of hyperpixels. Each of the sets of microLEDs 102includes a number of microLEDs 104A-104C, each of which emits adifferent color. For example, one microLED of each set (e.g., microLEDs104A) may emit red light, while another microLED of each set (e.g.,microLEDs 104B) may emit green light and the remaining microLED of eachset (e.g., microLEDs 104C) may emit blue light. Although as illustratedin FIG. 1 , the unit cell 100 includes three sets of microLEDs, it willbe recognized that more or fewer sets may be deployed in a single unitcell without departing from the spirit of embodiments described herein.For example, a single set of microLEDs with an integrated microlens maycomprise a unit cell. In accordance with embodiments described herein,while each set of microLEDs 102A-102C is shown in FIG. 1 as includingthree microLEDs that emit red, blue, and green light, respectively, itwill be recognized that each set may include greater or fewer than threemicroLEDs and that each LED of a set may emit a color other than red,blue, or green. Additionally, the order of LED colors may be differentthan as represented in FIG. 1 .

Referring again to FIG. 1 the unit cell 100 further includes one or morelenses, represented in FIG. 1 by lenses 106A-106C, disposed over thesets of microLEDs 102A-102C. In some embodiments, the lenses 106 may beshaped, configured and/or positioned to control a direction in whichlight is emitted from each set of microLEDs, as represented by arespective dashed line 108A-108C. In certain embodiments, each lens 106,is a positive lens and the sets of microLEDs 102 are disposed at or neara focal plane of the lens. The lens 106 may be formed from any materialable to adjust beam directionality, including an optical material suchas glass or plastic or a Fresnel or other diffraction lens, for example.

Each set of microLEDs 102 emits light of a tunable color and intensity.In particular, the intensity distribution of the light emitted throughthe lenses 106 can be managed by balancing the flux emitted from themicroLEDs 104 to correspond to a particular color. By using sufficientlyclosely spaced microLEDs of varying colors (e.g., RGB) within each set,the intensity distribution of RGB can be managed.

Although as shown in FIG. 1 , each set of microLEDs 102 has integratedtherewith a respective lens 106, it will be recognized that differentconfigurations may be provided, such as a single lens integrated overseveral sets of microLEDs and/or a lens integrated over each individualmicroLED.

Turning now to FIG. 2 , illustrated therein is a unit cell 200 forproviding an energy efficient, high contrast, highly responsive microLEDdisplay in accordance with features of embodiments described herein.Similar to the unit cell 100, the unit cell 200 represents one or morepixels in a display implemented using microLEDs in accordance withembodiments described herein. As shown in FIG. 2 , in an exampleembodiment, the unit cell 200 includes a number of sets of microLEDs202A-202C disposed on a substrate. Each set of microLEDs 202 includes anumber of individual microLEDs 204A-204D, each of which emits light of adifferent color. In particular, similar to the sets of microLEDs 102,the sets of microLEDs 202 includes a red microLED 204A, a green microLED204B, and a blue microLED 204C. In accordance with features ofembodiments described herein, the sets of microLEDs 202 further includean additional microLED 204D that emits yellow or amber light, forreasons that will be described in greater detail below. It will berecognized that the order of LED colors may be different than asrepresented in FIG. 2 . Although as illustrated in FIG. 2 , the unitcell 200 includes three sets of microLEDs, it will be recognized thatmore or fewer sets may be deployed in a single unit cell withoutdeparting from the spirit of embodiments described herein. For example,a single set of microLEDs with an integrated microlens may comprise aunit cell.

Referring again to FIG. 2 , the unit cell 200 further includes one ormore lenses, represented in FIG. 2 by lenses 206A-206C, disposed overthe sets of microLEDs 202A-202C, respectively. In some embodiments, thelenses 206 may be shaped, configured and/or positioned to control adirection in which a beam of light is emitted from each set ofmicroLEDs, as represented by a respective dashed line 208A-208C. Incertain embodiments, each lens 206, is a positive lens and the sets ofmicroLEDs 202 are disposed at or near a focal plane of the lens.

Each set of microLEDs 202 emits light of a tunable color and intensity.In particular, the intensity distribution of the light emitted throughthe lenses 206 can be managed by balancing the flux emitted from themicroLEDs 204 to correspond to a particular color, such as white. Byusing sufficiently closely spaced microLEDs of varying colors (e.g.,RGBY) within each set, the intensity distribution of RGBY can bemanaged.

Although as shown in FIG. 2 , each set of microLEDs 202 has integratedtherewith a respective lens 206, it will be recognized that differentconfigurations may be provided, such as a single lens integrated overseveral sets of microLEDs and/or a lens integrated over each individualmicroLED. Similarly, any number of different emission patterns may beprovided by various embodiments, depending on the configuration and/orplacement of the lens relative to the associated microLED(s). What isrelevant is that, in accordance with features of embodiments describedherein, a color of each pixel of a display is produced using acombination of emissions from some number of red, green, yellow, andblue InGaN microLEDs.

Turning now to FIG. 3A, illustrated therein is top schematic view of aportion of a microLED display 300 in accordance with embodimentsdescribed herein. As shown in FIG. 3A, the display 300 includes aplurality of unit cells 302 each of which is associated with andcorresponds to a pixel of the display 300. As represented by a pair ofarrows 304, light is emitted from each unit cell 302 as determined byits structure (i.e., the number of sets of microLEDs and the positioningof the lens(es)).

FIG. 3B is a side view of the display 300 shown in FIG. 3A. As shown inFIG. 3B, the unit cells 302 are disposed on a substrate 306 and each ofthe unit cells 302 has an emission pattern similar to that of the unitcells 100 and 200, illustrated in FIGS. 1 and 2 , although as notedabove, different emission patterns are anticipated and expecteddepending on the configuration of the unit cells 302 and application ofthe display 300. As shown in FIG. 3B, each pixel provides an angularemission intensity distribution corresponding to the emission pattern.

In various embodiments, the display 300 maybe advantageouslyincorporated into and/or deployed as a display for a variety of systems,devices and/or applications, including but not limited to smartphones(FIG. 4A), smart watches (FIG. 4B), and video display systems forvehicles such as automobiles and aircraft in which the display may hangfrom the ceiling of the vehicle and/or be incorporated into or otherwiseconnected to the back of a passenger seat (FIGS. 4C and 4D). That is, ina vehicle the microLED display can be positioned in one or morelocations within the vehicles for interior projection. Thus, in somecases the microLEDs may be used for illumination in various locations,such as seating and floor areas. The microLEDs may be used forillumination of internal or external features, such as door handles andmirrors, as well as display of electronic gauges and other vehicular orentertainment information. Projection and illumination sources can belocated in one or more locations within the vehicle, such as the roof,sides, rear, windows, seats or front (including the dashboard). Forgeneral illumination, the microLEDs may be used to outline or accentinterior areas or components and or illuminate these areas or occupants.Control of the vehicle interior lighting system may be based on vehiclecomputer input, such as speed and direction, external input, such asambient light and/or temperature, and/or user input via a user interfaceto the illumination source or user input device.

The International Commission on Illumination, or “CIE,” is aninternational standards organization that creates standards related tolight and color. CIE 1931 color spaces define quantitative links betweendistributions of wavelength in the visible spectrum and physiologicallyperceived colors in human color vision. The mathematical relationshipsthat define CIE color spaces are essential tools for color management inconnection with illuminated displays. FIG. 5 illustrates a CIE 1931chromaticity diagram 500. Chromaticity is an objective specification ofthe quality of a color regardless of its luminance. Chromaticityconsists of two independent parameters, often specified as hue andcolorfulness (which is also alternatively referred to as saturation,chroma, intensity, or excitation purity). The chromaticity diagram 500is a normalized plot of a standard observer, which each pointcorresponds to the color response of the CIE 1931 standard observer andrepresents the mapping of human color perception in terms of two CIEparameters x and y. The spectral colors are distributed along the edgeand include all of the perceived hues, providing a framework forinvestigating color.

As previously noted, pixels of a LED display are typically implementedusing LEDs of three primary colors: red, green, and blue. As shown inFIG. 5 , in the diagram 500, red, green, and blue form a triangle 501,with a point 502 of the triangle corresponding to red, a point 504 ofthe triangle corresponding to green, and a point 506 of the trianglecorresponding to blue. As will be known to one of ordinary skill in theart, colors within the triangle 501 may be reproduced by balancing thefluxes at the primary colors. As also shown in FIG. 5 , luminous flux ata white point 508 is ⅔ determined by green and ⅓ determined by red. Theside of the triangle 501 between the red point 502 and the green point504 comprises a red-green locus 510. A point 512 along the red-greenlocus 510 corresponds to yellow/amber.

Along the red-green locus, the effective EQE can be calculated from theLED properties. For example, referring to FIG. 6A, illustrated thereinis a graph 600 of the effective external quantum efficiency (EQE) of anInGaN microLED along the red-green locus. An x-axis of the graph 600corresponds to the dominant wavelength (in nanometers), while the y-axiscorresponds to the effective EQE. As shown in the graph 600, theeffective EQE at the green end of the locus is approximately 16%,whereas the effective EQE at the red end of the locus is just under 4%.If one were to use a dedicated single microLED along the green-redlocus, the EQE would behave approximately linearly, as shown in FIG. 6B,in which is illustrated a graph 610 of the EQE of an InGaN microLEDalong the red-green locus. An x-axis of the graph 610 corresponds to thedominant wavelength in nanometers, while the y axis corresponds to theEQE. Moreover, again assuming one were to use a dedicated singlemicroLED along the green-red locus, the EQE gain would be as shown inFIG. 6C, in which is illustrated a graph 620 of the EQE gain along thered-green locus. An x-axis of the graph 620 corresponds to the dominantwavelength (in nanometers), while the y-axis corresponds to the EQEpercentage gain.

FIG. 6D illustrates a graph 630 in which the gain along the red-greenlocus is expressed as lumens/watt (lm/W), with an x-axis of the graph630 corresponding to dominant wavelength in nanometers and a y-axis ofthe graph 630 corresponding to percentage gain in lm/W.

Such gain along the red-green locus translates into efficiency gain atthe white point. Gain in lm/W using red, green, and blue InGaN microLEDsto generate colors in a display is illustrated in a three-dimensionalgraph 700 shown in FIG. 7A. In contrast, gain (in lm/W) using red,yellow, green, and blue InGaN microLEDs to generate colors in a displayis illustrated in a three-dimensional graph 710 shown in FIG. 7B. Asillustrate in FIGS. 7A and 7B, the efficiency at the white point isincreased by nearly a factor of two; that is, from approximately 10% toapproximately 20% by the addition of a yellow/amber InGaN microLED foreach pixel, the efficiency of which is greater than that of the redInGaN microLED. In this manner, the effect of the low efficiency of redInGaN microLEDs on the overall efficiency of a display is diluted (i.e.,the overall efficiency of the display is improved) by the addition of ayellow/amber InGaN microLED to generate pixels using RGBY, rather thanmerely RGB.

FIG. 8 is a block diagram illustrating an example data processing system800 that may be configured to implement at least portions of a displayimplemented using microLEDs in accordance with embodiments describedherein, and more particularly as shown in the figures describedhereinabove.

As shown in FIG. 8 , the data processing system 800 may include at leastone processor 802, e.g. a hardware processor 802, coupled to memoryelements 804 through a system bus 806. As such, the data processingsystem may store program code within memory elements 804. Further, theprocessor 802 may execute the program code accessed from the memoryelements 804 via a system bus 806. In one aspect, the data processingsystem may be implemented as a computer that is suitable for storingand/or executing program code. It should be appreciated, however, thatthe data processing system 800 may be implemented in the form of anysystem including a processor and a memory that is capable of performingthe functions described within this disclosure, such as a smart phone, asmart watch, or a video display system, for example.

In some embodiments, the processor 802 can execute software or analgorithm to perform the activities as discussed in this specification,in particular activities related to a display implemented usingmicroLEDs in accordance with embodiments described herein. The processor802 may include any combination of hardware, software, or firmwareproviding programmable logic, including by way of non-limiting example amicroprocessor, a DSP, a field-programmable gate array (FPGA), aprogrammable logic array (PLA), an integrated circuit (IC), anapplication specific IC (ASIC), or a virtual machine processor. Theprocessor 802 may be communicatively coupled to the memory element 804,for example in a direct-memory access (DMA) configuration, so that theprocessor 802 may read from or write to the memory elements 804.

In general, the memory elements 804 may include any suitable volatile ornon-volatile memory technology, including double data rate (DDR) randomaccess memory (RAM), synchronous RAM (SRAM), dynamic RANI (DRAM), flash,read-only memory (ROM), optical media, virtual memory regions, magneticor tape memory, or any other suitable technology. Unless specifiedotherwise, any of the memory elements discussed herein should beconstrued as being encompassed within the broad term “memory.” Theinformation being measured, processed, tracked or sent to or from any ofthe components of the data processing system 800 could be provided inany database, register, control list, cache, or storage structure, allof which can be referenced at any suitable timeframe. Any such storageoptions may be included within the broad term “memory” as used herein.Similarly, any of the potential processing elements, modules, andmachines described herein should be construed as being encompassedwithin the broad term “processor.” Each of the elements shown in thepresent figures, e.g., any of the circuits/components shown in thefigures described above, can also include suitable interfaces forreceiving, transmitting, and/or otherwise communicating data orinformation in a network environment so that they can communicate with,e.g., the data processing system 800 of another one of these elements.

In certain example implementations, mechanisms for implementing adisplay implemented using microLEDs as outlined herein may beimplemented by logic encoded in one or more tangible media, which may beinclusive of non-transitory media, e.g., embedded logic provided in anASIC, in DSP instructions, software (potentially inclusive of objectcode and source code) to be executed by a processor, or other similarmachine, etc. In some of these instances, memory elements, such as e.g.the memory elements 804 shown in FIG. 8 , can store data or informationused for the operations described herein. This includes the memoryelements being able to store software, logic, code, or processorinstructions that are executed to carry out the activities describedherein. A processor can execute any type of instructions associated withthe data or information to achieve the operations detailed herein. Inone example, the processors, such as e.g. the processor 802 shown inFIG. 8 , could transform an element or an article (e.g., data) from onestate or thing to another state or thing. In another example, theactivities outlined herein may be implemented with fixed logic orprogrammable logic (e.g., software/computer instructions executed by aprocessor) and the elements identified herein could be some type of aprogrammable processor, programmable digital logic (e.g., an FPGA, aDSP, an erasable programmable read-only memory (EPROM), an electricallyerasable programmable read-only memory (EEPROM)) or an ASIC thatincludes digital logic, software, code, electronic instructions, or anysuitable combination thereof.

The memory elements 804 may include one or more physical memory devicessuch as, for example, local memory 808 and one or more bulk storagedevices 810. The local memory may refer to RAM or other non-persistentmemory device(s) generally used during actual execution of the programcode. A bulk storage device may be implemented as a hard drive or otherpersistent data storage device. The processing system 800 may alsoinclude one or more cache memories (not shown) that provide temporarystorage of at least some program code in order to reduce the number oftimes program code must be retrieved from the bulk storage device 810during execution.

As shown in FIG. 8 , the memory elements 804 may store an application818. In various embodiments, the application 818 may be stored in thelocal memory 808, the one or more bulk storage devices 810, or apartfrom the local memory and the bulk storage devices. It should beappreciated that the data processing system 800 may further execute anoperating system (not shown in FIG. 8 ) that can facilitate execution ofthe application 818. The application 818, being implemented in the formof executable program code, can be executed by the data processingsystem 800, e.g., by the processor 802. Responsive to executing theapplication, the data processing system 800 may be configured to performone or more operations or method steps described herein.

Input/output (I/O) devices depicted as an input device 812 and an outputdevice 814, optionally, can be coupled to the data processing system.Examples of input devices may include, but are not limited to, akeyboard, a pointing device such as a mouse, or the like. Examples ofoutput devices may include, but are not limited to, a monitor or adisplay, speakers, or the like. In particular, the output device 814includes features of one or more embodiments of a display implementedusing microLEDs in accordance with embodiments described herein. In someimplementations, the system may include a driver (not shown) for theoutput device 814. Input and/or output devices 812, 814 may be coupledto the data processing system either directly or through intervening I/Ocontrollers.

In an embodiment, the input and the output devices may be implemented asa combined input/output device (illustrated in FIG. 8 with a dashed linesurrounding the input device 812 and the output device 814). An exampleof such a combined device is a touch sensitive display, also sometimesreferred to as a “touch screen display” or simply “touch screen”. Insuch an embodiment, input to the device may be provided by a movement ofa physical object, such as e.g. a stylus or a finger of a user, on ornear the touch screen display.

A network adapter 816 may also, optionally, be coupled to the dataprocessing system to enable it to become coupled to other systems,computer systems, remote network devices, and/or remote storage devicesthrough intervening private or public networks. The network adapter maycomprise a data receiver for receiving data that is transmitted by saidsystems, devices and/or networks to the data processing system 800, anda data transmitter for transmitting data from the data processing system800 to said systems, devices and/or networks. Modems, cable modems, andEthernet cards are examples of different types of network adapters 816and include one or more physical jacks (e.g., Ethernet, USB, or Applelightning connectors) or one or more antennas to communicate to may beused with the data processing system 800. A display controller 820 mayalso be provided for purposes described hereinbelow.

The network adapter 816 may communicate over a communications network ordirectly utilizing any one or more of a number of wireless local areanetwork (WLAN) transfer protocols (e.g., frame relay, internet protocol(IP), transmission control protocol (TCP), user datagram protocol (UDP),hypertext transfer protocol (HTTP), etc.). Example communicationnetworks may include a local area network (LAN), a wide area network(WAN), a packet data network (e.g., the Internet), mobile telephonenetworks (e.g., cellular networks), Plain Old Telephone (POTS) networks,and wireless data networks. Communications over the networks may includeone or more different protocols, such as Institute of Electrical andElectronics Engineers (IEEE) 802.11 family of standards known as Wi-Fi,IEEE 802.16 family of standards known as WiMax, IEEE 802.15.4 family ofstandards, a Long Term Evolution (LTE) family of standards, a UniversalMobile Telecommunications System (UMTS) family of standards,peer-to-peer (P2P) networks, next generation (NG)/5^(th) generation (5G)standards, Zigbee, or Bluetooth, among others.

FIG. 9 provides a flow chart of a method 900 for operating a displayimplemented using microLEDs according to some embodiments of the presentdisclosure. At least portions of the method 900 may be implemented byelements according to any embodiment of the present disclosure, e.g., bya display implemented using microLEDs in accordance with embodimentsdescribed with reference to the above-described figures and/or by one ormore data processing systems, such as the data processing system 800shown in FIG. 8 . Although described with reference to system componentsof the systems shown in the present figures, any system, configured toperform operations of the method 900, in any order, is within the scopeof the present disclosure.

Referring to FIG. 9 , in step 901, a display is provided in which eachpixel is produced using a number of InGaN microLEDs, including at leasta red InGaN microLED, a green InGaN microLED, a yellow InGaN microLED,and a blue InGaN microLED. As previously noted, the addition of an InGaNmicroLED producing emissions along the red-green locus (e.g.,yellow/amber) improves the overall efficiency of a display in displayingcolors, as the higher efficiency yellow microLED reduces the impact ofthe lower efficiency red microLED. In step 902, a display controllerassociated with the display implemented using red, green, yellow/amber,and blue InGaN microLEDs according to some embodiments is provided withat least one data signal comprising at least a portion of at least oneimage to be presented on the display. In step 904, the displaycontroller (e.g., display controller 820) determines control signals forpresenting the at least one data signal on the display. In particular,the display controller determines an intensity and color to be emittedby each of the microLEDs for producing individual pixels comprisingunits of the at least one image to be presented on the display. In step906, the display controller provides the control signals to circuitryassociated with the RGBY microLEDs to cause the RGBY microLEDs to emitlight in accordance with the determined intensity and color (e.g.,white) for the respective pixel.

FIG. 10 is another block diagram illustrating a microLED display system1000 in accordance with embodiments described herein. As shown in FIG.10 , the display system may include a display 1002A on which images maybe presented. The system 1000 may further include a calibration andfeedback module 1004 for calibrating the system 1000, an image viewingsystem 1006 for generating 3D views, and a pixel controller 1008 havingaccess to image data 1010 for presentation on the display 1002A. In someembodiments, image or other data can be stored in an image frame buffer.If no changes in image data are to be used, one or more standby imagescan be directed to the image frame buffer. Such standby images caninclude, for example, an intensity and spatial pattern used for baselineor standard display or light projection. In operation, pixels in theimages are used to define response of corresponding microLED pixels,with intensity and spatial modulation of microLED pixels being based onthe image(s). To reduce data rate issues, groups of pixels orhyperpixels (e.g., square blocks of Y×Y pixels) can be controlled assingle blocks in some embodiments. The blocks may be used, for example3×3, 5×5, 7×7, or other sizes. High speed and high data rate operationcan be supported, with pixel values from successive images able to beloaded as successive frames in an image sequence at a rate between 24 Hzand 100 Hz, with 60 Hz being typical. Each microLED hyperpixel can beoperated to emit light in a pattern and with an intensity at leastpartially dependent on the image held in the image frame buffer.

The display 1002A may be a computer display, cell phone display, smartwatch display, or a vehicle display. In addition to the modulesdescribed in relation to FIG. 10 , the modules of the data processingsystem of FIG. 8 may be present. For example, the network adaptor ofFIG. 8 used in the system 1000 may be used for a smart watch tocommunicate with a paired smart phone via WiFi, while the networkadaptor may allow the smart watch to communicate with the network usinga 5G protocol.

It should be noted that, although the displays illustrated herein areshown as being rectangular and flat, the techniques described herein forimplementing a display using microLED technology are not so limited andmay be used to implement non-rectangular and/or curved displays asdesired.

Applications supported by the microLED pixels include both augmentedreality (AR) and virtual reality (VR). Various types of devices may beused to provide AR/VR to users, including headsets, glasses, andprojectors. Such an AR/VR system may have a microLED array containingthe microLED pixels, an AR or VR display (e.g., a headset or glasses), amicroLED array controller, sensors, and a system controller. The AR/VRsystem components can be disposed in a single structure, or one or moreof the components shown can be mounted separately. For example, a firstset of components, the microLED array, AR or VR display, and sensors canbe mounted on a single device, such as those above, while a second setof components, the microLED array controller and/or system controller,may be disposed separately from the first set of components andconnected via wireless communication.

User data input provided to the system controller can includeinformation provided by audio instructions, haptic feedback, eye orpupil positioning, or connected keyboard, mouse, or game controller. Thesystem controller controls the microLED array controller based onsignals from the sensors. The sensors may include cameras, depthsensors, audio sensors, accelerometers, two or three axis gyroscopes andother types of motion and/or environmental/wearer sensors. The sensorsmay also be configured to receive a control input. Other sensors caninclude air pressure, stress sensors, temperature sensors, or any othersuitable sensors needed for local or remote environmental monitoring. Insome embodiments, the control input can include detected touch or taps,gestural input, or control based on headset or display position. Asanother example, based on the one or more measurement signals from oneor more gyroscope or position sensors that measure translation orrotational movement, an estimated position of the AR/VR system relativeto an initial position can be determined. Thus, movement of the person(or head) can be detected and the image displayed can be changedaccordingly.

As above, the microLED array can support hundreds, thousands, or evenmillions of microLEDs positioned together on centimeter scale areasubstrates or smaller. The microLED array can be monochromatic, RGB, orother desired chromaticity. The pixels of the microLED array can besquare, rectangular, hexagonal, or have curved perimeter. Pixels can beof the same size, of differing sizes, or similarly sized and grouped topresent larger effective pixel size and controlled via a ComplementaryMetal Oxide Semiconductor (CMOS) backplane, for example. In someembodiments, separate microLED arrays can be used to provide displayimages, with AR features being provided by a distinct and separatemicroLED array.

In some embodiments, the microLED array controller may control one groupof pixels to be used for displaying content (AR/VR and/or non-AR/VR) tothe user while controlling another group of pixels to be used astracking pixels for providing tracking light used in eye tracking toadjust the content. Content display pixels are designed to emit lightwithin the visible band (approximately 400 nm to 780 nm). Trackingpixels may be designed to emit visible light and/or light in the IR band(approximately 780 nm to 2,200 nm). In some embodiments, the trackingpixels and content pixels may be simultaneously active. In someembodiments, the tracking pixels may be controlled to emit trackinglight during a time period that content pixels are deactivated and arethus not displaying content to the user. The microLED array controllermay control the image displayed based on the x, y, z position of theviewer as determined by the system controller (using sensor data andperhaps user input data) and indicated to the microLED array controller.

In some embodiments, the microLED pixels and circuitry supportingmicroLED array can be packaged and include a submount or printed circuitboard for powering and controlling light production by the microLEDs.The printed circuit board supporting the microLED array may includeelectrical vias, heat sinks, ground planes, electrical traces, and flipchip or other mounting systems. The submount or printed circuit boardmay be formed of any suitable material, such as ceramic, silicon,aluminum, etc. If the submount material is conductive, an insulatinglayer may be formed over the substrate material, and a metal electrodepattern formed over the insulating layer for contact with the microLEDarray. The submount can act as a mechanical support, providing anelectrical interface between electrodes on the microLED array and apower supply, and also provide heat sink functionality.

The AR/VR system can incorporate lens as described above in the microLEDarray and/or AR/VR display to couple light emitted by microLED arrayinto the AR/VR display. Each lens can have at least one coating, such asa UV blocking or anti-reflective coating. In some embodiments, thelenses may be designed to polarize the light transmitted therethrough.The lenses in other embodiments include one an aperture and/or filter.The lenses, instead of directing light from the microLEDs, as describedabove, can be used to magnify and/or correct images, such as correctionor minimization of various two- or three-dimensional optical errors.

In one embodiment, the microLED array controller may provide power andreal time control for the light emitting array. For example, themicroLED array controller may implement individual pixel-level or grouppixel-level control of amplitude and duty cycle. The microLED arraycontroller may contain a frame buffer for holding generated or processedimages that can be supplied to the microLED array. The microLED arraycontroller and/or system controller may include digital controlinterfaces such as an Inter-Integrated Circuit serial bus, SerialPeripheral Interface (SPI), USB-C, HDMI, Display Port, or other suitableimage or control modules that are configured to transmit image data,control data or instructions.

In some embodiments, the system controller may use data from the sensorsto integrate measurement signals received from the accelerometers overtime to estimate a velocity vector and integrate the velocity vectorover time to determine an estimated position of a reference point forthe AR/VR system. The system controller may also provide an initialcalibration mentioned above. In other embodiments, the reference pointused to describe the position of the AR/VR system can be based on depthsensor, camera positioning views, or optical field flow. Based onchanges in position, orientation, or movement of the AR/VR system, thesystem controller can send images or instructions the light emittingarray controller. Changes or modification the images or instructions canalso be made by user data input, or automated data input.

In one embodiment, intensity can be separately controlled and adjustedby setting appropriate ramp times and pulse width for each microLEDpixel using a logic and control module and the pulse width modulationmodule. This allows staging of LED pixel activation to reduce powerfluctuations, and to provide various pixel diagnostic and calibrationfunctionality.

It should be noted that, although the displays illustrated herein areshown as being rectangular and flat, the techniques described herein forimplementing a display using microLED technology are not so limited andmay be used to implement non-rectangular and/or curved displays asdesired.

Other than display applications, various applications can be supportedby microLED pixel or hyperpixel array systems such as described herein.Light emitting pixel arrays may support any applications that benefitfrom fine-grained intensity, spatial, and temporal control of lightdistribution. This may include, but is not limited to, precise spatialpatterning of emitted light from pixel blocks or individual pixels.Depending on the application, emitted light may be spectrally distinct,adaptive over time, and/or environmentally responsive. The lightemitting pixel arrays may provide pre-programmed light distribution invarious intensity, spatial, or temporal patterns. The emitted light maybe based at least in part on received sensor data and may be used foroptical wireless communications. Associated optics may be distinct at apixel, pixel block, or device level. An example light emitting pixelarray may include a device having a commonly controlled central block ofhigh intensity pixels with an associated common optic, whereas edgepixels may have individual optics. Common applications supported bylight emitting pixel arrays include video lighting, automotiveheadlights, architectural and area illumination, street lighting, andinformational displays.

Light emitting pixel arrays may be used to selectively and adaptivelyilluminate buildings or areas for improved visual display or to reducelighting costs. In addition, light emitting pixel arrays may be used toproject media facades for decorative motion or video effects. Inconjunction with tracking sensors and/or cameras, selective illuminationof areas around pedestrians may be possible. Spectrally distinct pixelsmay be used to adjust the color temperature of lighting, as well assupport wavelength specific horticultural illumination.

Street lighting is an important application that may greatly benefitfrom use of light emitting pixel arrays. A single type of light emittingarray may be used to mimic various streetlight types, allowing, forexample, switching between a Type I linear street light and a Type IVsemicircular street light by appropriate activation or deactivation ofselected pixels. In addition, street lighting costs may be lowered byadjusting light beam intensity or distribution according toenvironmental conditions or time of use. For example, light intensityand area of distribution may be reduced when pedestrians are notpresent. If pixels of the light emitting pixel array are spectrallydistinct, the color temperature of the light may be adjusted accordingto respective daylight, twilight, or night conditions.

Light emitting arrays are also well suited for supporting applicationsrequiring direct or projected displays. For example, warning, emergency,or informational signs may all be displayed or projected using lightemitting arrays. This allows, for example, color changing or flashingexit signs to be projected. If a light emitting array is composed of alarge number of pixels, textual or numerical information may bepresented. Directional arrows or similar indicators may also beprovided.

Vehicle headlamps are a light emitting array application that requireslarge pixel numbers and a high data refresh rate. Automotive headlightsthat actively illuminate only selected sections of a roadway can used toreduce problems associated with glare or dazzling of oncoming drivers.Using infrared cameras as sensors, light emitting pixel arrays activateonly those pixels needed to illuminate the roadway, while deactivatingpixels that may dazzle pedestrians or drivers of oncoming vehicles. Inaddition, off-road pedestrians, animals, or signs may be selectivelyilluminated to improve driver environmental awareness. If pixels of thelight emitting pixel array are spectrally distinct, the colortemperature of the light may be adjusted according to respectivedaylight, twilight, or night conditions. Some pixels may be used foroptical wireless vehicle to vehicle communication.

It is to be understood that not necessarily all objects or advantagesmay be achieved in accordance with any particular embodiment describedherein. Thus, for example, those skilled in the art will recognize thatcertain embodiments may be configured to operate in a manner thatachieves or optimizes one advantage or group of advantages as taughtherein without necessarily achieving other objects or advantages as maybe taught or suggested herein.

It should be appreciated that the electrical circuits of theaccompanying drawings and its teachings are readily scalable and canaccommodate a large number of components, as well as morecomplicated/sophisticated arrangements and configurations. Accordingly,the examples provided should not limit the scope or inhibit the broadteachings of the electrical circuits as potentially applied to a myriadof other architectures.

In some embodiments, any number of electrical circuits of theaccompanying drawings may be implemented on a board of an associatedelectronic device. The board can be a general circuit board that canhold various components of the internal electronic system of theelectronic device and, further, provide connectors for otherperipherals. More specifically, the board can provide the electricalconnections by which the other components of the system can communicateelectrically. Any suitable processors (inclusive of digital signalprocessors, microprocessors, supporting chipsets, etc.),computer-readable non-transitory memory elements, etc. can be suitablycoupled to the board based on particular configuration needs, processingdemands, computer designs, etc. Other components such as externalstorage, additional sensors, controllers for audio/video display, andperipheral devices may be attached to the board as plug-in cards, viacables, or integrated into the board itself. In various embodiments, thefunctionalities described herein may be implemented in emulation form assoftware or firmware running within one or more configurable (e.g.,programmable) elements arranged in a structure that supports thesefunctions. The software or firmware providing the emulation may beprovided on non-transitory computer-readable storage medium comprisinginstructions to allow a processor to carry out those functionalities.

In some embodiments, the electrical circuits of the accompanyingdrawings may be implemented as stand-alone modules (e.g., a device withassociated components and circuitry configured to perform a specificapplication or function) or implemented as plug-in modules intoapplication specific hardware of electronic devices. Note that someembodiments of the present disclosure may be readily included in asystem on chip (SOC) package, either in part, or in whole. An SOCrepresents an integrated circuit (IC) that integrates components of acomputer or other electronic system into a single chip. It may containdigital, analog, mixed-signal, and often radio frequency functions: allof which may be provided on a single chip substrate. Other embodimentsmay include a multi-chip-module (MCM), with a plurality of separate ICslocated within a single electronic package and configured to interactclosely with each other through the electronic package. In various otherembodiments, features may be implemented in one or more silicon cores inApplication Specific Integrated Circuits (ASICs), Field ProgrammableGate Arrays (FPGAs), and other semiconductor chips.

It is also important to note that the functions related to embodimentsdescribed herein include only some of the possible functions that may beexecuted by, or within, the systems described herein. Some of theseoperations may be deleted or removed where appropriate, or theseoperations may be modified or changed considerably without departingfrom the scope of the present disclosure. In addition, the timing ofthese operations may be altered considerably. The preceding operationalflows have been offered for purposes of example and discussion.Substantial flexibility is provided by embodiments described herein inthat any suitable arrangements, chronologies, configurations, and timingmechanisms may be provided without departing from the teachings of thepresent disclosure.

Numerous other changes, substitutions, variations, alterations, andmodifications may be ascertained to one skilled in the art and it isintended that the present disclosure encompass all such changes,substitutions, variations, alterations, and modifications as fallingwithin the scope of the appended claims. Note that all optional featuresof any of the devices and systems described herein may also beimplemented with respect to the methods or processes described hereinand specifics in the examples may be used anywhere in one or moreembodiments.

1. An apparatus comprising: a lighting arrangement comprising aplurality of pixels, each pixel comprising a set of LEDs, each set ofLEDs comprising at least a first LED configured to emit light of a firstwavelength, a second LED configured to emit light of a secondwavelength, a third LED configured to emit light of a third wavelength,and a fourth LED configured to emit light along a locus between thefirst wavelength and the second wavelength to increase efficiency at awhite point from each pixel to compensate for reduced external quantumefficiency (EQE) of the first LED compared with an EQE of at least oneof the second LED and an EQE of the third LED; and a controllerconfigured to control at least one of individual pixels and individualhyperpixels, each hyperpixel comprising a unique set of the pixels. 2.The apparatus of claim 1, wherein the controller is configured tocontrol a status of each of the individual pixels to enable a beamemitted from the individual pixel to appear to be steered withoutphysical movement of the individual pixel, the status selected fromactivation, deactivation, and dimming to an intermediate value ofintensity.
 3. The apparatus of claim 1, wherein the controller isconfigured to control a status of each of the individual hyperpixels toenable a beam emitted from the individual hyperpixel to appear to besteered without physical movement of the individual hyperpixel, thestatus selected from activation, deactivation, and dimming to anintermediate value of intensity.
 4. The apparatus of claim 3, whereinthe controller is configured to control a beam intensity of a beamemitted from each of the individual hyperpixels by adjustment of anumber of pixels that forms the beam.
 5. The apparatus of claim 1,wherein at least some of the individual pixels have a same size.
 6. Theapparatus of claim 1, wherein at least some of the individual pixelshave different sizes.
 7. The apparatus of claim 1, wherein theindividual hyperpixels are formed as a square block of the pixels. 8.The apparatus of claim 1, wherein the lighting arrangement furthercomprises a plurality of lenses, each lens arranged to control emissionangles and emission profiles of light of a unique set of LEDs.
 9. Theapparatus of claim 1, wherein the apparatus is integrated into aportable electronic device.
 10. A system comprising: a displaycomprising a plurality of pixels, each pixel comprising a set of LEDs,each set of LEDs comprising at least a first LED configured to emitlight of a first wavelength, a second LED configured to emit light of asecond wavelength, a third LED configured to emit light of a thirdwavelength, and a fourth LED configured to emit light along a locusbetween the first wavelength and the second wavelength to increaseefficiency at a white point from each pixel to compensate for reducedexternal quantum efficiency (EQE) of the first LED compared with an EQEof at least one of the second LED and an EQE of the third LED; sensorsconfigured to capture at least one of motion and environmentalinformation; and a system controller configured to control at least oneof individual pixels and individual hyperpixels based on input from thesensors to provide one of an augmented reality (AR) or virtual reality(VR) output, each hyperpixel comprising a unique set of the pixels. 11.The apparatus of claim 10, wherein the controller is configured tocontrol a status of each of the individual pixels to enable a beamemitted from the individual pixel to appear to be steered withoutphysical movement of the individual pixel, the status selected fromactivation, deactivation, and dimming to an intermediate value ofintensity.
 12. The apparatus of claim 10, wherein the controller isconfigured to control a status of each of the individual hyperpixels toenable a beam emitted from the individual hyperpixel to appear to besteered without physical movement of the individual hyperpixel, thestatus selected from activation, deactivation, and dimming to anintermediate value of intensity.
 13. The apparatus of claim 12, whereinthe controller is configured to control a beam intensity of a beamemitted from each of the individual hyperpixels by adjustment of anumber of pixels that forms the beam.
 14. The system of claim 10,wherein the display further comprises a plurality of lenses, each lensarranged to control emission angles and emission profiles of light of aunique set of LEDs.
 15. The system of claim 10, wherein the sensorscapture user inputs further used by the system controller to control theindividual pixels or individual hyperpixels.
 16. The system of claim 10,wherein the system controller is configured to control content displaypixels to display at least one of AR or VR content and tracking pixelsto track eye movement to adjust the at least one of AR or VR content.17. The system of claim 16, wherein the system controller is configuredto control the content display pixels to emit light within a visibleband and the tracking pixels to emit light in an infrared bandsimultaneously with the content display pixels.
 18. The system of claim16, wherein the system controller is configured to control the contentdisplay pixels and the tracking pixels to emit light within a visibleband such that the tracking pixels emit the light during a time periodwhen the content pixels are deactivated.
 19. A method for operating adisplay, the method comprising: determining an image to present on thedisplay; and driving a plurality of pixels to provide the image, eachpixel comprising a set of LEDs, each set of LEDs comprising a first LEDconfigured to emit light of a first wavelength, a second LED configuredto emit light of a second wavelength, a third LED configured to emitlight of a third wavelength, and a fourth LED configured to emit lightalong a locus between the first wavelength and the second wavelength toenhance efficiency at a white point from each pixel to compensate forreduced external quantum efficiency (EQE) of the first LED compared withan EQE of at least one of the second LED and an EQE of the third LED,the plurality of pixels controlling at least one of individual pixelsand individual hyperpixels, each hyperpixel comprising a unique set ofthe pixels to control a respective color produced by each of the atleast one of individual pixels and individual hyperpixels.
 20. Themethod of claim 19, wherein controlling the at least one of individualpixels and individual hyperpixels comprises controlling a status of eachof the individual pixels to enable a beam emitted from the individualpixels to appear to be steered without physical movement of theindividual pixel, the status selected from activation, deactivation, anddimming to an intermediate value of intensity.